Dementia is a term used to describe a group of conditions characterised by the gradual impairment of brain function. It is commonly associated with memory loss, but can affect speech, cognition (thought), behaviour and mobility. An individual’s personality may also change, and health and functional ability decline as the condition progresses.

While there are many forms of dementia, the best known is Alzheimer’s disease—a degenerative brain disease caused by nerve cell death resulting in shrinkage of the brain. The boundaries between different forms of dementia are indistinct and it is possible for a person to have multiple (mixed) types of dementia at the same time.

Although dementia can affect younger people, it is increasingly common with advancing age and mainly occurs among those aged 65 and over, but is not a normal part of ageing. Dementia is a major cause of disability and dependency among older people. It not only affects individuals with the condition, but also has a substantial impact on their families and carers, as people with dementia eventually become dependent on their care providers in most, if not all, areas of daily living.

How common is dementia?

The exact number of people with dementia in Australia is currently not known. It is estimated that in 2020 there are between 400,000 and 459,000 Australians with dementia (AIHW 2018; DA 2020), with Alzheimer’s disease accounting for up to 70% of diagnosed cases (DA 2018).

Measuring dementia prevalence

The estimates vary because national data for the prevalence of dementia are not readily available. As a result, current estimates are based on rates derived from published international and local studies that have been applied to the Australian population, and the method in which they have been applied to the Australian context differs between sources. See ‘Dementia data in Australia—understanding gaps and opportunities’ in Australia’s health 2020: data insights for more information.

It is expected that the continued growth and ageing of Australia’s population will lead to an increase in the number of people with dementia over time, as the condition is increasingly common with advancing age and primarily affects older people. The number of people with dementia is expected to increase to between 550,000 (AIHW 2018; Figure 1) and 590,000 by 2030 (DA 2020).
 

This graph shows the estimated and projected prevalence of dementia by age group between 2010 and 2030. The first bar on the left shows that the estimated prevalence of dementia across all ages was almost 300,000 persons in 2010 and it is projected to increase to around 550,000 persons by 2030. The estimated number of persons with dementia aged under 65 increases from about 23,000 to about 29,000 across the 20 years, while the number of persons with dementia aged 65 to 84 and 85 and over increases more markedly across the 20 years.

See International comparisons of health data for information on how the prevalence of dementia in Australia compares with other countries. Note, the Australian dementia prevalence rates shown in the international comparisons section are produced by the Organisation for Economic Co-operation and Development (OECD). These rates differ from the Australian dementia prevalence estimates described in this section due to methodological differences. The OECD dementia prevalence rates are used for international comparisons only.

Risk factors

A range of factors are known to contribute to the risk of dementia and may affect the progression of its symptoms. Some risk factors can’t be changed, such as age, genetics and family history. However, several are modifiable, and can be altered to prevent or delay dementia. High levels of education, physical activity and social engagement are all protective against developing dementia, while smoking, hearing loss, depression, diabetes, hypertension, and obesity are all linked to an increased risk of developing dementia (Livingston et al. 2017).

Impact

Deaths

Dementia was the second leading cause of death in Australia in 2018, accounting for almost 14,000 deaths (ABS 2019). For females, dementia was the leading cause of death (nearly 9,000 deaths), while it was the third leading cause for males (nearly 5,000 deaths).

Between 2008 and 2017, the number of deaths where dementia was an underlying cause increased by 68% (Figure 2). Further, the dementia death rate grew from 33 deaths per 100,000 people to 42. This may reflect not only an increase in the number of older people with dementia, but also changes in how dementia deaths are recorded.

See Causes of death.
 

This graph shows the number and age-standardised rates of dementia deaths by males, females and persons. The age-standardised rates follow a similar pattern for both males and females, overall increasing between 2008 and 2017, with females consistently having higher rates than males. From 2008 to 2017, the age-standardised rate for all persons increased from 33 to 42 per 100,000 population.

Burden of disease

Burden of disease refers to the quantified impact of a disease or injury on an individual or population. Dementia was the fourth leading cause of disease and injury burden among the Australian population in 2015, and was responsible for 3.8% of the total burden of disease and injury, equal to 179,804 disability-adjusted life years (DALY). The burden from dementia accounted for a greater proportion of the total burden for females than males, accounting for 5.0% of total DALY for females and 2.7% for males. This is influenced by the fact that women live longer than men and therefore are more likely to develop dementia. Females comprised 52% of dementia hospitalisations (Figure 3) and 58% of people dispensed anti-dementia medicines in 2017–18.

As expected, the dementia burden was also higher among people aged 65 and over, for whom it was the second leading cause of total burden of disease and injury (7.7% of total DALY) (AIHW 2019c).

See Burden of disease.

Expenditure

The Australian Disease Expenditure Study estimated that about $428 million in health expenditure (excluding aged care expenditure) was attributable to dementia in Australia in 2015–16, with $5.5 million more spent on females than males. More than $324 million was spent on hospital-related services for people with dementia—which includes both public and private sectors and admitted and non-admitted care. Public hospital admitted patients were the largest contributor to hospital expenditure, accounting for $212 million. Almost $90 million was spent on public hospital outpatient services, around $17 million on private hospital services, and $5.1 million was spent on public hospital emergency department services. Public hospital outpatient expenditure was higher for females than for males (about $49 million for females compared with about $41 million for males). However, public hospital admitted patient expenditure was higher for males—$112 million was spent on the care of males compared with $100 million on females (AIHW 2019d).

In the same year (2015–16), more than $40 million was spent on medicines for people with dementia. About half of this was for 4 specific medicines that are prescribed to treat Alzheimer’s disease—Donepezil, Galantamine, Rivastigmine and Memantine (see the blue box below for more information on these medicines) (AIHW 2019b). Services provided by specialists accounted for more than $16 million while general practitioner services accounted for almost $23 million, and $3.1 million was spent on allied health and other services. About $13 million was spent on general practitioner services for females compared with $9.6 million for males (AIHW 2019d).

See Health expenditure.

Treatment and management

Hospitalisations

In 2017–18, dementia was recorded as the principal and/or additional diagnosis in 93,800 hospitalisations (Figure 3). Although more than half of these hospitalisations involved females (52%), after accounting for differences in age and population size, males were 1.3 times as likely to be hospitalised with dementia as females. The majority of people hospitalised with a principal and/or additional diagnosis of dementia were aged 85–94 (43%), while 3.3% were under 65 and 4.6% were over 95.

See Hospital care.

Trends in hospitalisations

The number of hospitalisations where dementia was recorded as the principal and/or additional diagnosis fluctuated between 2008–09 and 2017–18, from about 86,700 to 93,800 (Figure 3). Overall, the rate of hospitalisations involving dementia decreased by 17% in this period—from 357 to 296 hospitalisations per 100,000 population.

It is not clear why there has been a decrease in the rate of dementia hospitalisations, however some of the decrease may be due to changes to the way dementia is coded in hospitals data. For example, in 2015, 29 supplementary codes for chronic conditions (including dementia) and a new Australian Coding Standard were implemented in the International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Australian Modification, 9th edition, and the Australian Coding Standards, which are used to record diagnoses in hospitals data (see AIHW 2019a for further information). Further research is required to determine the influence, if any, of the supplementary codes on the coding of hospitalisations for dementia as this section includes dementia hospitalisations as the principal and/or additional diagnosis only.

Hospitalisations for individual types of dementia (principal and/or additional diagnosis) also changed over time. While the number of hospitalisations involving unspecified dementia decreased by 42%, there was an increase in the number of hospitalisations involving vascular dementia (79%), Alzheimer’s disease (39%) and delirium superimposed on dementia (310%).

Similar to the trends in the number of hospitalisations by dementia type, there was a decrease in the age-adjusted rate of hospitalisations involving unspecified dementia (56%), and an increase in the age-adjusted rate for hospitalisations involving vascular dementia (39%), Alzheimer’s disease (6%) and delirium superimposed on dementia (211%).

The large increase in the number and rate of hospitalisations involving delirium superimposed on dementia may be a result of a marked increase in awareness and education for delirium during this decade (Department of Health and Ageing 2011; Department of Health & Human Services 2011).
 

This graph shows the number and age-standardised rates of dementia hospitalisations by dementia type and sex between 2008–09 and 2017–18. This figure has filters for comparing by financial year, dementia type, sex and the measure (number or age-standardised rate). The age-standardised rate for any dementia decreased from 357 per 100,000 in 2008–09 to 296 in 2017–18; the rate of hospitalisations for Alzheimer’s disease remained steady (78 and 83 per 100,000 in 2008–09 and 2017–18, respectively); the rate of hospitalisations for vascular dementia increased from 31 to 43 per 100,000; the rate of delirium superimposed on dementia also increased from 18 to 56 per 100,000; and the rate of hospitalisations with unspecified dementia decreased markedly from 207 per 100,000 in 2008–09 to 91 per 100,000 in 2017–18

Hospitalisations by remoteness and socioeconomic areas

After accounting for age and population size, those living in Major cities were 1.2 times as likely to be hospitalised with dementia as those living in Inner regional and outer regional areas in 2016–17. Those living in Remote and very remote areas had a similar likelihood of being hospitalised with dementia to those living in Major cities. People living in the lowest socioeconomic areas were 1.1 times as likely to be hospitalised with dementia as those living in the highest socioeconomic areas (AIHW 2019e).

Medicines

Although there is no cure for dementia, anti-dementia medicines can be used to alleviate some of the symptoms of dementia. This section covers the 4 medicines used to treat Alzheimer’s disease that are subsidised by the Australian Government through the Pharmaceutical Benefits Scheme and Repatriation Pharmaceutical Benefits Scheme.

Anti-dementia medicines

Cholinesterase inhibitors: Donepezil, Galantamine and Rivastigmine

Cholinesterase inhibitors are a class of anti-dementia medicine that prevent the breakdown of acetylcholine, an important component in cognitive pathways in the brain. Levels of acetylcholine decrease in people with Alzheimer’s disease and some other dementias. By increasing the availability of acetylcholine in the brain, these medicines are thought to improve or stabilise cognitive function in people with dementia.

N-methyl-D-aspartate (NMDA) receptor antagonist: Memantine

Memantine is a type of anti-dementia medicine that blocks the functioning of NMDA receptors and reduces the levels of glutamate in the brain, thereby preventing the movement of excess calcium in the brain. Increased levels of glutamate in the brain may contribute to the symptoms and progression of Alzheimer’s disease and other dementias. NMDA receptor antagonists are thought to improve or stabilise cognitive function in people with Alzheimer’s disease, with improvements seen in the function of daily activities, thinking and behaviour.

About 572,000 prescriptions for anti-dementia medicines were dispensed to 60,900 people aged 30 and over with a diagnosis of Alzheimer’s disease in 2017–18 (Figure 4).

See Medicines in the health system.

Medicines by age, sex and medicine name

Of people aged 30 and over and using anti-dementia medicines, 59% were women and 42% were men. After accounting for differences in age and population size, men and women were dispensed anti-dementia medicines at similar rates (3 and 4 per 1,000 population, respectively). The majority (63%) of people on anti-dementia medicines were aged 65–84, with 4.0% aged 30–64 and 32% aged over 85.

In 2017–18, the medication dispensed most often was Donepezil (66%), followed by Galantamine (14%), Rivastigmine (12%) and Memantine (8.5%) (Figure 4). The supply of all 4 types of anti-dementia medications was higher among women than men.
 

This graph shows the number of prescriptions for dispensed anti-dementia medicines, by medicine, sex and age. Donepezil was the most dispensed anti-dementia medicine for persons aged 30 and over (376,000 scripts), followed by Galantamine (78,000 scripts), Rivastigmine (69,000 scripts) and Memantine (48,000 scripts). The supply of all four types of anti-dementia medicines was higher among females than males; females were dispensed 336,000 scripts and males 236,000 scripts.

Aged care

Aged care services are an important resource for both people with dementia and their carers. Services include those provided in the community for people living at home (home support and home care), and residential aged care services for those requiring permanent care or short-term respite stays. While aged care service use data provide some insights into the care needs of people with dementia accessing these services, they may underestimate the number of people with dementia.

About 107,000 people were using home care at 30 June 2019. Of these people, around 9% received the dementia and cognition supplement, a payment for people with moderate to severe levels of cognitive impairment associated with dementia or other conditions.

At 30 June 2019, about 183,000 people were in permanent residential aged care, and just over half (53%) had been diagnosed with dementia. The care needs of people in permanent residential care are assessed through the Aged Care Funding Instrument (ACFI) across 3 domains of care: activities of daily living, cognition and behaviour, and complex health care. The care needs in each domain are allocated a rating of nil, low, medium, or high. In 2019, people with dementia had higher care needs ratings than people without dementia on the activities of daily living and cognition and behaviour care domains; the differences were largest for the cognition and behaviour domain, where nearly twice as many people with dementia (80%) had high care needs compared with people without dementia (46%). A similar proportion of people with and without dementia had high care needs in the complex health care domain (AIHW 2020a, 2020b).

See ‘Changes in people’s health service use around the time of entering permanent residential aged care’ in Australia’s health 2020: data insights.

Where do I go for more information?

For more information on dementia, see:

Visit Dementia for more on this topic.

References

ABS (Australian Bureau of Statistics) 2019. Causes of death, Australia, 2018. ABS cat. no. 3303.0. Canberra: ABS.

AIHW (Australian Institute of Health and Welfare) 2018. Australia’s health 2018. Australia’s health series no. 16. Cat. no. AUS 221. Canberra: AIHW.

AIHW 2019a. Admitted patient care 2017–18: Australian hospital statistics. Health services series no. 90. Cat. no. HSE 225. Canberra: AIHW.

AIHW 2019b. Disease Expenditure Database: findings based on unit record analysis. Canberra: AIHW.

AIHW 2019c. Australian Burden of Disease Study: impact and causes of illness and death in Australia 2015. Australian Burden of Disease series no. 19. Cat. no. BOD 22. Canberra: AIHW.

AIHW 2019d. Disease expenditure in Australia. Cat. no. HWE 76. Canberra: AIHW.

AIHW 2019e. Hospital care for people with dementia 2016–17. Cat. no. AGE 94. Canberra: AIHW.

AIHW 2020a. GEN dashboard 2018–19: People using aged care 2018–19. Canberra: AIHW.

AIHW 2020b. GEN fact sheet 2017–18: People’s care needs in aged care. Canberra: AIHW.

DA (Dementia Australia) 2018. Alzheimer’s disease. Australia: DA.

DA 2020. Dementia statistics. Australia: DA.

Department of Health and Ageing 2011. Delirium care pathways. Canberra: Department of Health and Ageing.

Department of Health & Human Services 2011. Clinical Practice Guidelines for the Management of Delirium in Older People 2006. Victoria: Department of Health & Human Services.

Livingston G, Sommerlad A, Orgeta V, Costafreda SG, Huntley J, Ames D et al. 2017. Dementia prevention, intervention, and care. The Lancet 390:2673–734.